Three-dimensional (3D) integrated circuit (IC) devices utilize stacked wafers and/or dies that are vertically interconnected using through-silicon vias (TSVs), so that the wafers or dies perform as a single device. 3D ICs can provide enhanced performance, with reduced power usage (and a smaller footprint) than conventional two-dimensional IC devices. 3D ICs generally have functional capabilities such as logic and/or memory capabilities. Reduced-capability 3D ICs, which are also referred to in the art as 2.5D ICs, can have similar construction as their 3D counterparts, but may have relatively diminished capabilities. These 2.5D ICs may include interposers or other passive devices.
In any case, 3D ICs and 2.5D ICs are becoming more prevalent in the semiconductor industry due in part to their ability to handle complex tasks within a small package. However, these more compact devices present greater challenges in terms of design, scaling and interconnection of components. For example, in terms of TSVs, it may be difficult to locate and fabricate particular types of TSVs for specific functions (e.g., power or signal) given the compact nature of 3D ICs and 2.5D IC devices.